Liquid developing apparatus

ABSTRACT

Apparatus for developing diazo-sensitized copy material by the application thereto of a quantity of developer liquid includes an applicator roller to the surface of which there is supplied developer liquid, a wiper member movably mounted for engagement with the roller surface to wipe excess developer liquid therefrom and a pressure applying member movably mounted for engagement with the roller surface to form a developing zone therewith through which sensitized copy material is passed for development. A rotatably cam member and electrical circuit arrangement function in combination to move the wiper and pressure applying member into engagement with the roller surface upon operating the apparatus to an on condition, and out of engagement upon operating the apparatus to an off condition.

3,687,049 Aug. 29, 972

[54] LIQUID DEVELOPING APPARATUS Y FOREIGN PATENTS 0R APPLICATIONS 72 Inventors Robert M. Koch,'Wheaton; Samuel 232,858 4/1964 Austria......................95/89 A Primary Examiner-Samuel S. Matthews I Assistant Examiner-Fred L. Braun Att0meySol L. Goldstein Cor- 4 poration, Mount Prospect, 11].

April 27, 1970 [22] Filed: ABSTRACT developing diazo-sensitized copy material by the application thereto of a quantity of r m m P P A. M%9 R BXGX 2. 4 /5 9 696 B JZ Z L 1 6 "898 s 29 l 1 o m m 1 TA W mmmm 1.1 "u R W 9 M A G P m QPW y mHSv ee 9 W0 m MMM 1 .13 9 M GPWM a s "m e D 5480 m m R 6365 .m 9999 o. m mwmw N. QL l 1 p m 0. Snub. 7180 A uir mmmm m mum 2,955, [[rL 3 32 developer liquid includes an applicator roller to the surface of which there is supplied developer liquid, a wiper member movably mounted for engagement .with the roller surface to wipe excess developer liquid therefrom and a pressure applying member movably mounted for engagement with the roller surface to form a developing zone therewith through which sen- I sitized copy material is passed for development. A rotatably cam member and electrical circuit arrange ment function in combination to move the wiper and pressure applying member into engagement with the roller surface upon operating the apparatus to an on condition, and out of engagement upon operating the apparatus to an off condition.

3,453,138 7/1969 Chenetal.................95/89R 2,946,307 7/1960 Warner..................l18/259 X 18 Claims, 4 Drawing Figures SHEET 1 0F 3 v sum 2 or '3 mm m2 mjw 0 I BACKGROUND OF THE INVENTION This invention relates generally to apparatus for.

developing diazotype copy material and more particularly to apparatus of the above-mentioned type which applies a liquid developing agent in metered quantities to exposed diazo-sensitized copy material, thereby to produce dry-to-the-touch developed copies.

The. method of developing diazo-sensitized copy material by the application of relatively small, metered quantities of liquid developer is described in US. Pat. No. 3,446,620, issued May 27, 1969, and assigned to the same assignee.

Apparatus for carrying out the above-described method is also disclosed in US. Pat. Application Ser. No. 831,685, filed June 9,1969, now US. Pat. No. 3,626,833 and Serial No. 831,399, filed June 9, 1969, now U.S.-Pat. No. 3,640,203 assigned to the same as,-

- signee.

In the-last-mentioned applications there is described developing apparatus comprising an applicator roller which has a uniquely prepared surface adapted to receive and carry a limited quantity of developer fluid. Against the surface of the applicator roller and parallel to the axis of rotation thereof, is a mechanical wiper used for removing excess fluid.from the applicator roller surface. ,A second, pressure applying-roller is in driving engagement with the applicator roller to form a developing zone therebetween. Copy material fed between the rollers is developed by the application of the liquid under pressure provided by, the pressure roller.

The apparatus of the aforementioned application operates well to provide fully developed, dry-to-thetouch copies with a minimum of developing fluid. However, in the case wherein very wide diazo copy material (i.e., in the range of 40 plus inches) is to bedeveloped, applicator and pressure rollers must also be of lengths equal to or greater than the width of the material.

In practice a pressure roller used in the abovedescribed apparatus weighs approximately 1 pound for each inch of length. Thus, a roller of 40 plus inches would weigh 40 or more pounds. The great weight of such a roller member presents engineering problems in that added support is required for the roller members and greater costs for the fabrication of such an apparatus would be incurred.

In addition to the last-mentioned problems, because of the'length of the rollers, irregularities in the surfaces, non-uniform pressures therebetween along the lengths of the rollers and/or curves in the rollers'themselves which occur in fabrication or during use, might tend to produce a non-uniform application of developer fluid to copy material passing through the developing zone, resulting utimately in unacceptable, non-uniformly developed copies.

SUMMARY OF THE INVENTION Accordingly, it is a general object of the present in vention to provide new and improved apparatus of the general type described for developing diazo-sensitized copy material which avoids the drawbacks discussed.

It is a more specific object of the invention to provide an apparatus of the last-mentioned type which can be used successfully and efficiently in the development of plicator roller member adapted to carry a limited quan- 2 relatively wide diazo-sensitized copy material by applying uniformly thereto, a predetermined quantity of liquid developing agent.

Briefly, a preferred embodiment of the developing apparatus according to the invention comprises an. ap

tity of developer fluid and mounted for rotation. Adjacent the surface of the applicator roller and extending the length of and parallel thereto, is a pressure applying blade mounted for tangential engagement with the roller surface, the area between the blade and roller surface forming a copy material developing zone. A second, fluid metering blade is also mounted. for tangential engagement with the surface of the applicator roller. The second blade is mounted 180 about the applicator roller from the first-mentioned blade to equalize the forces applied to the roller. A fluid carrying member, substantially equal in length to the applicator roller, is located in the area between the fluid applying blade and the applicator roller. A series of holes is 7 formed in the member, from which fluid is pumped onto the metering blade member. The fluid is dispersed by the blade member over the surface of the roller, and the excess fluid wiped from the roller surface by the fluid metering blade is carried into a trough beneath the applicator-roller.

. To insure the uniform dispersion of developing fluid over the roller surface and to prevent fluid droplets from building upin the developing zone between the applicator roller surface and the pressure applying blade, provision is made to move the pressure applying blade, into engagement with the roller surface a predetermined time after engagement of the wiper blade with the roller surface; sufficiently long to meter a uniform layer of fluid onto the roller surface. The latter is accomplished automatically by means of a novel electrical circuit and control-linkage arrangement upon energization of the power switch of the developer apparatus. The blades are likewise removed sequentially from contact with the roller surface upon deenergization of the apparatus. Removal of the blades from contact with the applicator roller surface when- DESCRIPTION OF THE DRAWINGS A better understanding of the present invention and its organization and construction may be had by referring to the description below in conjunction with the accompanying drawings wherein:

FIG. 1 is a plan view of a diazotype copying machine incorporating the developing apparatus according to the invention;

FIG. 2 is a side sectional view of the copying machine of FIG. 1;

FIG. 3 is an enlarged side view of the cam driver used for moving the metering and pressure applying blades of the developing apparatus into and out of engagement with the surface of the developer fluid applicator roller taken along the line 3-3 of FIG. I; and

FIG. 4 is a schematic diagram of the electrical circuitry for operating the developer apparatus in accordance with the present invention.

3 DETAILED DESCRIPTION The copying machine comprises a housing 14 including front and rear walls l6, 18, upper and lower walls 20, 22, and side walls 24, 26, interconnecting the upper, lower, front and rear walls.

A lower section 28 of the housing (FIG. 2) includes copy sheet exposure apparatus 30 for exposing a diazosensitized copy sheet to light while the copy sheet is in surface-to-surface contact with an original tracing, for the purpose of imaging the copy sheet.

The particular copy sheet exposure apparatus shown in FIG. 2 of the drawings comprises a rotatable lamp 32 about the outer surface'34 of which is carried a sandwiched copy sheet and original tracing (not shown) for exposure of the former. An endless belt 36 extends about the outer surface of the lamp 32 and is also mounted for movement along rollers 38, 40, and 42. A smaller roller 44 provides tension to the belt36 to insure that the latter is in close contact with the lamp 32.

The sandwiched original tracing and copy sheet are fed over shelf 45 into an entrance 46 adjacent roller 42 between belt 36 and outer surface 34 of lamp 32. The original and copy sheet are carried about lamp 32 and depart at exit 48 adjacent roller 38. At this point the copy sheet has been exposed. The copy sheet is separated from the original tracing, and is now ready for development.

In the upper section 50 of the copying machine housing 14, there is located a preferred embodiment of the developing apparatus 112 according to the invention.

The developing apparatus 12 comprises an applicator roller 52 having a central shaft portion 54 of metal and anouter or peripheral layer 56 of a smooth nonporous, resilient material such as rubber. The outer surface 58 of the peripheral layer 56 is specially prepared to form a developer fluid carrier surface having irregular depressions of varying depths and sizes. A more detailed description of the carrier surface will be given hereinafter.

Roller 52 is mounted for rotation at ends 60, 62 of shaft portion 54 between vertically extending walls 64, 66, in bearings 68, 70 mounted on the walls (FIG. 1). An extension member 72, including a sprocket wheel 74 is mounted at end 62 of shaft 54. A drive motor 76 provides the power for driving the applicator roller 52 through shaft 78 extending from the gear train 79 of motor 76, and including a sprocket drive wheel 80 mounted thereon. An endless chain 75 connected to the aforementioned sprocket wheels serves to transfer the power provided by motor 76 to the applicator roller 52 for rotation of the latter.

The chain 75 also extends about sprocket wheels 82, 84 which are mounted on shafts 83, 85, respectively, extending from wall 66. The last-mentioned wheels provide a path over which endless chain 75 moves to drive applicator roller 52.

Positioned on opposite sides of roller 52, spaced 180 from each other thereabout, is a pair of blade members 86, 88, respectively. Each of the blade members 86, 88 is mounted on a respective rotatable support herein taking the form of a tubular shaft 90, 92, by means of a blade holder member 94, 96 attached thereto, respec- 4 tively. The blades, each fabricated from a flat length of spring steel or the like material, are fastened to a respective blade holder member by fasteners, such as bolts 98.

The shafts 90,92, which are also mounted between walls 64, 66 are rotatable in the direction of the arrows (FIG. 2) to cause blade members 86, 88 to engage the surface 58 of roller 52, as shown in dotted lines. As can be seen, the blade members are caused to be bowed when in contact with the roller surface to make tangential contact therewith.

A tubular conduit 100 mounted on an L shaped bracket 102, connected to blade holder member 94 is provided to dispensedeveloper of roller 52. A flexibletube 104 coupled at one end 106 of dispenser tube 100 is connected via developer fluid pump 108 to a reservoir 109 Fluid pumped through tube 104 exits from tubular conduit 100 through spaced apertures 103 (FIG. 2) provided in the wall thereof. 7

Developer liquid dispensed from the tube 100 is I poured onto the surface 112 of blade 86, and upon the latter making engagement with the surface of rotating roller 52, is applied or metered onto the roller surface 58.

Metering blade member 86 together with the roller 52 having the specially prepared surface 58 delivers a controlled amount of developer fluid to a copy sheet being developed. The blade member 86 wipes away excess developer fluid which in turn runs back into a trough 114 mounted beneath the applicator roller and metering blades. The excess fluid is channeled through an opening 116 in trough 114, (FIG. 2), and through a screen-like filter 1 11 to the fluid reservoir 109 so that it may be reused. The filter screen 111 serves to remove minute paper particles which may have found their way into the developer fluid during the development process, and which, if not removed, could eventually become lodged beneath the blade members, causing streaks along the surface of subsequently developed copy sheets. Cleaning of the filter screen 111 periodically to remove the paper particles build up thereon is desirable.

As mentioned heretofore, the surface 58 of the applicator roller 52 is specially prepared to carry a predetermined quantity of developer liquid used to develop diazo-sensitized copy sheets.

The texture or finish of the applicator roller 52 is important to the successful operation of the developer apparatus. The amount of developer fluid retained on the roller surface 58 and carried to the copy sheet being developed is dependent on the surface characteristics of the roller. It has been found that the surface best suited for carrying the proper amount of liquid for development of dry-to-the-touch copy sheets is one of varying depths and sizes providing a predetermined degree of average center line smoothness expressed in terms of micro-inches in depth. It has been concluded that an applicator roller having a center line average smoothness in the range of 10 200 micro-inches provides a satisfactory finish according to the invention.

The limits of fluid application provided by a properly liquid to the surface 58 of fluid developer 110.

For a more detailed description of the roller surface and its preparation, the readers attention is directed to US. Pat. applications,'Ser. Nos., 831,685 and 831,399 assigned to the same assignee.

Thev second blade member 88, when engaged with roller surface 58, applies to the latter surface pressure along a line of contact therewith equal to the force applied by blade member 86, 180 about the roller 52. The contactarea forms a developing zone 118, (FIG. 2) through which copy sheets are passed to be developed. a 1

It is important that the forces applied to the roller surface are equal. If they are not, a tendency for the roller to shift will be prevalent as well as a possible disfiguration of the surfaceof the roller. In both of the last-mentioned. cases, the ultimate quality of copies produced in the developer will be affected.

A copy sheetentering the developing apparatus at entrance 120 is manually urged upwardly along curved guide member 122 mounted on fixture 119 within section 50 of the housing (FIG. 2) into the developing zone 118, whereat the leading edge of the paper is gripped between the pressure applying blade member 88 and the roller 52. The rotation of roller 52 in the direction indicated by the'arrow, transports the copy sheet through zone 118 whereat developer fluid is applied in printing fashion, to the imaged copy sheet. The developed copy sheet emerges from the developing apparatus at exit 124 in a dry-to-the-touch condition.

As mentioned heretofore, the blade members 86, 88 are each mounted on members 90, 9 2 respectively, which can be rotated to cause the engagement and disengagement of the blade members withthe surface 58' of applicator roller 52.

The physical movement of the blade members is controlled by a control-linkage and electrical contact assembly 126, shown in greater detail in FIGS. 3 and 4 of the drawings.

The previously mentioned assembly 126 includes a control-linkage member, preferably taking the form of a cam member 128 having a generally circular'shape and mounted for rotation at the center 130 thereof to the shaft 132 of an electrically operated motor 134 (FIG. 1) capable of being operated in a forward (engage) and reverse (release) direction by means of motor engage and release coils, respectively, to be discussed hereinafter.

Two sets of electrical contact arrangements 136, 138, each including two pairs of leaf spring contacts 136a, 1136b and 138a, 138b, respectively, are mounted, by means of insulating mounting arrangements 137, 139, respectively, of the well known type, adjacent cam member 128 at opposite sides thereof (180 about the circumference of the cam member). The contacts are operated by means of cam follower rollers 140, 142, connected to the stacked contacts by means of additional lead springs 143, 145, respectively. Each of the rollers rides along the external surface or edge 147 of the cam member 128. Lead wires as seen in FIG. 3, are connected to the terminal ends of the respective contacts. The actual connections to contacts 136a, 136b, and 138a 1382: will be described hereinafter when discussing the circuit diagram of FIG. 4.

The cam member is constructed to include three outer track portions, T1, T2, T3, each at a different,

136, 138 are opened or closed, as the case may be, to in turn energize of deenergize motor 134.

Apair of arms 144, 146, each of which is pivotally connected at a first end 149, 151, respectively, by

' fasteners 148, 150 (FIGS. 1 and 3) to a respective end 7 152, 154 (FIG. 1) of one of the rotatable tubular shafts 90, 92, is provided to translate the rotatable movement of the cam member 128 into a driving force for movement of the blade members 86, 88. The opposite ends I 156,158 of arms'l44, 146 are each coupled by a cam follower wheel or roller 160, 162 respectively, to cam memberv 128. The last-mentioned wheels being mounted for rolling engagement in specially designed cut-outs or tracks 164, 166 in cam member 128. Each of the tracks 164, 166 includes a passive track portion P1, P2 and an active portion A1, A2, respectively. Movement of the rollers 160, 162 along the passive portions of the, tracks 164, 166, causes no physical movement of the respective blade members, and movement in the active portions of tracks 164, 166 causes the blades to be moved into or out of engagement with the applicator roller surface 58, depending upon the direction of rotation (clockwise or counterclockwise) of cam member 128. The operation of the cam member 128 and followers will be explained hereinafter.

Turning now to FIG. 4 of the drawings, there is illustrated therein a preferred embodiment 170 of the circuit-for controlling the movement of the blade members 86, 88 into and out of engagement with the applicator roller 52.

The circuit 170 is powered by a conventional 115 volt AC source, (not shown) connected across terminals 172, 174 each of which is in turn connected to a lead 176, 178, respectively. Lead 176 is connected to a first armature 180 of the manual operated-on-off switch 182. Switch armature 180 is normally connected to a first contact 184 which is in turn connected to a lead wire 186. The last-mentioned wire 186, is connected to normally open contacts 138a of leaf contact spring pair 138.

A second contact 188 of the manual on-off switch 180 is provided for connection with armature 180. The movement of armature 180, to contact 188 supplies power via lead 183 to operate pump motor 108, thereby to begin pumping fluid to the tube member 1011 (FIG. 1) and to begin the movement of blades 86, 88. Pump motor 108 is connected back to the power source via lead 178. The movement of switch arm 180 to contact 188 also provides power from the source to energize drive motor 76 for rotating applicator roller 52.

The contacts 138a, connected to manual on-off switch 182 via lead 186,-are connected via lead 192 to motor release coil 190 of motor 134 which in turn is connected through leads 194, 196, back to the AC 7 power source.

'contact pair 136, and, leads 202through switch contacts 13611 of contact pair 136,

via lead 204 to the normally closed sets of contacts 206 of a three second time delay relay 208. The armature [207 of relay 208 is connected back to switch contact 188 of switch 182 via lead 209.

The normally open contacts 210 of relay 208 are connected via lead 212, through normallyclosed contacts 138b and lead 214 to motor engage coil 216. The I last-mentioned coil is connected back to the power source via leads 196,178.

Normally closed contacts 138b are connected also via lead 218 through normally closed contacts 136a of Y220 and 204 to the normally closed contacts-206 of time delay relay 208.

For purposes of affording a more complete unis in the unoperated, normal state. When it is desired to operate the developer apparatus of theinvention, the manual on-off switch 182is depressed, causing armature 180 thereof to be moved from contact 184 to contact 188, opening the connection to lead 186 and closing operating circuits to pump motor 108 drive motor 76 and a circuit via lead 290 and the normally closed contacts206 of time delay relay 208. t I At this time applicator roller 52 starts to rotate and fluid begins to be pumped from the reservoir 110 to tube 100 for distribution onto blade 86 and over the surface of the applicator roller.

Poweris applied through the normally closed con tacts of relay 208, via lead 204 through lead 220 and normally closed contacts 136a and leads 218 and 214- to the motor engage coil 216 to begin rotation of cam 128 in the direction of arrow 224 (FIG. 3). The cam is rotated approximately 40 in the counterclockwise direction as seenin FIG. 3 to an intermediate position. As the cam turns, 147 thereof.

Roller 140 remains on the track T1 for a time but then moves to track T2, whereby contact 136a is caused to be opened. The opening of switch 136a (FIG. 4) deenergizes the engage coil 216 to stop the rotation of cam 128'. At this time switch contacts 136a, 136b are both in an open condition since roller 140 is at rest on track T2. The roller 142 also moves from the track T3 to T2, and causes contacts 138a to be closed. At this time both contacts 138a, 138b are in a closed condition.

During the 40 rotation of cam 128, rollers 160 and 162 also were moved along respective cut-outs 164, 166 in cam 128. Roller 160 moved along the passive portion P1 of cut-out 164 while roller 162 moved along the active portion A2 of cut-out 166; thus, developer fluid metering blade 86, FIG. 1 is brought into engagement with the applicator roller surface.

During the 3 second delay time of relay 208, developer fluid flowing from apertures 103 in feed tube 100, is metered over the surface 58 of roller 52. After the 3 second delay time is completed, relay armature 207, moves from normally closed contact 206 to normally open contact 210. Power from the 115 volt AC source now is provided again through closed contacts 1138b to motor engage coil 216, once again to cause the rollersl40, 142 roll'along the edge 8 rotation of cam member'128. in the direction (counterclockwise) of arrow 224 (FIG. 3). t

The cam member 128 this time rotates an additional 80 from its intermediate position. During the 80 rotation, roller 142 moves from track T2 to track Tl,

whereby switch contacts 138!) are opened. e V

The opening of contacts 138b breaks the connection from the power source to the engage coil 216, deenergizing motor 134 and stopping the rotation of cam member-128.

During the last-mentioned 80'- rotation of cam member 128, roller 162 was moved thro ughthe passive portion P2 of cu't-out166, so that no additional mov'e- I ment of blade member 86 was effected. Roller 160,

however, was moved through the active portion A1 of cut-out 164, causing the pressureapplying blade member 88-to be moved into engagement with the surface of applicator roller 52.

Once both blades are in engagement with the rotating applicator roller, the developing apparatus is deemed to be in a running condition, and diazo copies direction opposite to the direction indicated by arrow is operated to an off condition. While the preferred means for moving the blade may be fed through the developer section 50 of the diazo copying machine'10 (FIG. 2) for processing.

Upon completion of the developing process, the developing apparatus is restored to its normal unoperatedstate by operation of the manual on ofi switch 182 to its off position. In doing so, armature 180 of the switch is moved from engagement with contact 188 into engagement with contact 184, and armature 198 thereof is moved out of engagement with contact 200.

A connection is now made from. the volt AC sourceto motor release coil 190. The connection is from the source via leads 176, 186, through contacts 138a which remain closed because of the position of roller 142 on the track T1, and lead 192. With motor release coil 190 energized, motor 134 (FIG. 1) is operated to rotate cam' member 128 in a clockwise 224. The cam is rotated a full back to the home or normal position.

During the last-described rotation, blade members 86, 88 are sequentially removed from engagement with the applicator roller, blade member 88 being disengaged first, followed by blade member 86. This movement occurs because of the movement of rollers 160, 162 through the active and passive portions of the respective cut-outs in reverse order from that explained for the initial operating cycle.

Once returned to the home position, contacts 138a are opened to stop the motor 134, and pump motor 108 members 86, 88 into and out of engagement with the applicator roller 52 are the cam and circuit arrangement described above, it will "be understood that such sequential movement could be obtained by other means, such as, for example, a series of gears arranged to control the movement of the blade members with a time delay arrangement operating the drive mechanism for the gears. It is therefore contemplated to cover by the present application any such equivalent means.

It has been explained that a preferred developing apparatus according to the invention includes means for moving the blade members 86, 88 into and out of engagement with the applicator roller sequentially as described. Such sequential movement is important since it affords a uniform wetting of the applicator roller prior to bringing the pressure applying blade member into contact with the roller, thereby to allow for a faster starting time as well as to prevent contact of the blade member against a relatively dry roller surface which might have a detrimental effect thereon.

While it is preferred in the subject apparatus to move the pressure applying and wiper blade members toward and away from the applicator roller, the result achieved thereby can also be achieved through movement of the roller toward and away from the blade members, as well as through the movement of both the blades members and the roller toward and away from each other.

What we claim is:

1. Apparatus for developing sensitized sheet material by the application to said material of a predetermined quantity of developer liquid, said apparatus comprismg:

- a liquid applicator roller'mounted for rotation, said roller having a surface adapted to carry a predetermined quantity of developer liquid,

means for rotating said roller during the processing of copies and for stopping the rotation of said roller when copies are not being processed,

wiper means mounted for engagement with said roller surface for removing excess developer liquid therefrom,

pressure applying means mounted for engagement with said roller surface and forming therebetween a developing zone through which sensitized sheet material is passed for development, and

circuit control means for moving both said wiper means and pressure applying means toward and away from said roller surface in response to the rotational and non-rotational movement, respectively, of said roller surface.

2. Apparatus as claimed in claim 1 wherein said wiper means and pressure applying means are sequentially moved into engagement with said roller surface upon the operation of said apparatus, said wiper means being moved into engaging relation with said rotating roller prior to said pressure applying means, whereby a uniform layer of developer liquid is applied thereby to said roller surface before saidpressure applying means engages said roller surface.

3. Apparatus for developing sensitized sheet material by the application to said material of a predetermined amount of developer liquid, said apparatus comprising;

an applicator roller mounted for rotation, said roller having a surface adapted to carry a predetermined quantity of developer liquid,

a source of developer liquid for application to said applicator roller surface,

wiper means for removing excess developer liquid from the surface of said roller, said wiper means mounted adjacent said roller for movement into and out of engagement with said roller surface, pressure applying means mounted adjacent said roller for movement into and out of engagement with said roller surface, said pressure applying ing means and wiper means to be moved into en-- gagement with said roller surface upon placing said apparatus into the operative condition, and out of engagement with said roller surface upon placing said apparatus into the inoperative condition.

4. Apparatus as claimed in claim 3 further including means for dispensing developer. liquid from said source to said roller surface said dispensing means being in communication with said source of liquid and being coupled to said circuit control-means for operation thereby, said dispensing means 'being operated to dispense liquid developer from said source upon said apparatus being operated to an operative condition,

- and to cease dispensing liquid'upon the operation of means and said roller forming a developing zone along a line of contact therebetween through which said sensitized sheet material is passed for development,

said apparatus to an inoperative condition.

5. Apparatus as claimed in claim 4 further including means for rotating said applicator roller, said means being coupled to and controlled by said circuit control means, whereby said roller is rotated upon placing said apparatus into an operating condition and said roller ceases to be rotated whensaid apparatus is in an in operative condition.

6. Apparatus for developing sensitized sheet material by the application to said material of a predetermined amount of developer liquid, said apparatus comprising:

an applicator roller mounted for rotation, said roller having a surface adapted to carry a predetermined quantity of developer liquid, a source of developer liquid for application to said applicator roller surface,

wiper means for removing excess developer liquid from the surface of said roller, said wiper means mounted adjacent said roller for movement into and out of engagement with said roller surface,

pressure applying means mounted adjacent said roller for movement into and out of engagement with said roller surface, said pressure applying means and said roller forming a developing zone along a line of contact therebetween through which said sensitized sheet material is passed for development,

means for moving said pressure applying means and wiper means into and out of engagement with said roller surface, and

circuit control means for operating said apparatus between an operative condition and an inoperative condition, said circuit control means coupled to said moving means for causing said pressure applying means and wiper means to be moved into engagement with said roller surface upon placing said apparatus into the operative condition, and out of engagement with said roller surface upon placing said apparatus into the inoperative condition,

wherein said means for moving said pressure applying means and wiper means into and out of engagement' with said roller includes a cam member mounted for rotational movement, and coupled to each of said pressure applying and wiper means, whereby upon rotation of said cam member in a first direction said pressure applying and wiper means are moved into engagement with said roller surface, and upon rotation of said cam member in the opposite direction, said pressure applying and wiper means are moved out of engagement with said roller, wherein said cam member is driven rotatably by motor means, and wherein said circuit control means interconnects said motor means to a source of electrical power, said circuit control means including switch means movable to an on position, whereby said motor means is operated electrically to rotate said cam member in said first direction and to an off position, whereby said motor means is operated electrically to rotate said cam member in said opposite direction.

7. Apparatus as claimed in claim 6 wherein said circuit control means comprises a plurality of contacts coupled mechanically to said cam member and electrically to said motor means, said contacts being operable by the rotation of the cam member a predetermined distance in said first direction, to cause said motor means to discontinue operation, thereby to prevent further rotation of said cam member in said first direction.

,8. Apparatus as claimed in claim 7 wherein said contacts are of the elongated resilient type mounted at one end to support means located adjacent said rotating cam member, and at the other end to a cam follower, said follower being in engagement with said cam member for movement thereover as said cam member is rotated, and wherein said cam member includes a plurality of track portions over which said follower is movable, said contacts remaining in an operated condition to maintain said motor meansoperational so long as said. follower is engaging a predetermined one of said track portions, but being moved to an unoperated condition upon engagement of said follower with another one of said track portions, whereby the operation of said motor means is discontinued.

9. Apparatus as claimed in claim 7 wherein said contacts are operable by the rotation of said cam member in said opposite direction to discontinue the operation of said motor means upon said cam member returning to its initial position.

10. Apparatus as claimed in claim 9 wherein said cam member is coupled to each of said pressure applying and wiper means by a corresponding arm member, a first one of said arm members being connected at a first end to said pressure applying means and a second one of said arm members being connected at a first end to said wiper means, said opposite ends of said arm members each being connected to respective follower portions mounted for movement on first and second track portions, respectively, on said cam member each said track portion including a passive section and an active section, whereby movement of a follower portion in said active section causes, through a respective arm member, movement of a corresponding pressure applying or wiper means toward or away from said roller surface, depending upon the direction of rotation of said cam member.

11. Apparatus as claimed in claim 10 wherein the cam follower of said second arm member is moved over said active section of the track portion initially during the rotation of said cam member in said first direction and wherein the cam follower of said first arm member is moved over said active section of the track portion at a subsequent time during the rotation of said cam member in said first direction, whereby said wiper means is moved into engagement with said roller surface a predetermined time prior to said pressure applying means. 7

12. Apparatus as claimed in claim 6 wherein said wiper means and pressure applying means are moved into engagement withsaid roller surface in sequence,

14. Apparatus for developing sensitized sheet materi- I al by the application to said material of a predeter-.

mined quantity of developer liquid, said apparatus comprising:

an applicator roller mounted for rotation, said roller having a surface adapted to carry a predetermined quantity of developer liquid,

means for rotating said applicator roller in a predetermined direction,

a source of developer liquid for application to said applicator roller surface,

a wiper blade for removing excess developer liquid from the surface of said roller, said wiper blade mounted adjacent said roller on a support member, said support member being rotatable toward and away from said roller surface for engagement and disengagement, respectively, of said wiper blade, with said roller surface,

a pressure blade mounted adjacent said roller on a support member, said support member being rotatable toward and away from said roller surface for engagement and disengagement, respectively, of said pressure blade with said roller surface,

a cam member mounted for rotation adjacent said roller and coupled to each of said support members, means for rotating said cam member to provide movement of said blades through said support members,

and control means for operating said apparatus, in-

cluding electrical circuit means connected to said means for rotating said applicator roller and said means for rotating said cam member, said electrical circuit means including switch means actuable to on and off positions whereby upon actuation of said switch means to the on position, said applicator roller is caused to be rotated and said cam member is rotated to move said blades into engagement with said roller surface, and upon actuation of said switch to the off position the rotation of said applicator roller ceases and said blades are moved out of engagement with said roller surface.

developer liquid onto said wiper blade for application thereby to said roller surface, and pump means interconnecting said source and said dispensing means, and wherein said pump .means is coupled to said control means, whereby upon operation of said switch means to said on position, said pump means is activated to pump developer liquid from said source to said dispensing means, and upon operation of said switch to said off position, said pump means is deactivated.

16. Apparatus as claimed in claim 14 wherein said wiper and pressure blade support members are connected to said cam member by means of arm members, each of said arm members being connected .pivotally' at a first end to said support member and connected at the opposite end to said cam member, whereby rotational movement of said cam member is translated through said arm members 'to said blade support members.

17. Apparatus as claimed in claim 16 wherein said electrical circuit means includes contact means operated in accordance with the rotation of said cam member, and wherein said cam member is rotated by means of motor means coupled electrically to said contact means and said switch means, whereby upon the actuation of said switch means said motor means is energized to rotate said' cam member in a first direction, said contact means being operable inresponse to the rotation of said cam member a predetermined distance in said first direction to deenergize said motor means, thereby preventing further rotation of said cam member.

18. Apparatus as claimed in claim 14 wherein said wiper blade is moved into engagement with said roller surface a predetermined time prior to said pressure blade. 

1. Apparatus for developing sensitized sheet material by the application to said material of a predetermined quantity of developer liquid, said apparatus comprising: a liquid applicator roller mounted for rotation, said roller having a surface adapted to carry a predetermined quantity of developer liquid, means for rotating said roller during the processing of copies and for stopping the rotation of said roller when copies are not being processed, wiper means mounted for engagement with said roller surface for removing excess developer liquid therefrom, pressure applying means mounted for engagement with said roller surface and forming therebetween a developing zone through which sensitized sheet material is passed for development, and circuit control means for moving both said wiper means and pressure applying means toward and away from said roller surface in response to the rotational and non-rotational movement, respectively, of said roller surface.
 2. Apparatus as claimed in claim 1 wherein said wiper means and pressure applying means are sequentially moved into engagement with said roller surface upon the operation of said apparatus, said wiper means being moved into engaging relation with said rotating roller prior to said pressure applying means, whereby a uniform layer of developer liquid is applied thereby to said roller surface before said pressure applying means engages said roller surface.
 3. Apparatus for developing sensitized sheet material by the application to said material of a predetermined amount of developer liquid, said apparatus comprising: an applicator roller mounted for rotation, said roller having a surface adapted to carry a predetermined quantity of developer liquid, a source of developer liquid for application to said applicator roller surface, wiper means for removing excess developer liquid from the surface of said roller, said wiper means mounted adjacent said roller for movement into and out of engagement with said roller surface, pressure applying means mounted adjacent said roller for movement into and out of engagement with said roller surface, said pressure applying means and said roller forming a developing zone along a line of contact therebetween through which said sensitized sheet material is passed for development, means for moving said pressure applying means and wiper means into and out of engagement with said roller surface, and circuit control means for operating said apparatus between an operative condition and an inoperative condition, said circuit control means coupled to said moving means for causing said pressure applying means and wiper means to be moved into engagement with said roller surface upon placing said apparatus into the operative condition, and out of engagement with said roller surface upon placing said apparatus into the inoperative condition.
 4. Apparatus as claimed in claim 3 further including means for dispensing developer liquid from said source to said roller surface said dispensing means being in communication with said source of liquid and being coupled to said circuit control means for operation thereby, said dispensing means being operated to dispense liquid developeR from said source upon said apparatus being operated to an operative condition, and to cease dispensing liquid upon the operation of said apparatus to an inoperative condition.
 5. Apparatus as claimed in claim 4 further including means for rotating said applicator roller, said means being coupled to and controlled by said circuit control means, whereby said roller is rotated upon placing said apparatus into an operating condition and said roller ceases to be rotated when said apparatus is in an inoperative condition.
 6. Apparatus for developing sensitized sheet material by the application to said material of a predetermined amount of developer liquid, said apparatus comprising: an applicator roller mounted for rotation, said roller having a surface adapted to carry a predetermined quantity of developer liquid, a source of developer liquid for application to said applicator roller surface, wiper means for removing excess developer liquid from the surface of said roller, said wiper means mounted adjacent said roller for movement into and out of engagement with said roller surface, pressure applying means mounted adjacent said roller for movement into and out of engagement with said roller surface, said pressure applying means and said roller forming a developing zone along a line of contact therebetween through which said sensitized sheet material is passed for development, means for moving said pressure applying means and wiper means into and out of engagement with said roller surface, and circuit control means for operating said apparatus between an operative condition and an inoperative condition, said circuit control means coupled to said moving means for causing said pressure applying means and wiper means to be moved into engagement with said roller surface upon placing said apparatus into the operative condition, and out of engagement with said roller surface upon placing said apparatus into the inoperative condition, wherein said means for moving said pressure applying means and wiper means into and out of engagement with said roller includes a cam member mounted for rotational movement, and coupled to each of said pressure applying and wiper means, whereby upon rotation of said cam member in a first direction said pressure applying and wiper means are moved into engagement with said roller surface, and upon rotation of said cam member in the opposite direction, said pressure applying and wiper means are moved out of engagement with said roller, wherein said cam member is driven rotatably by motor means, and wherein said circuit control means interconnects said motor means to a source of electrical power, said circuit control means including switch means movable to an on position, whereby said motor means is operated electrically to rotate said cam member in said first direction and to an off position, whereby said motor means is operated electrically to rotate said cam member in said opposite direction.
 7. Apparatus as claimed in claim 6 wherein said circuit control means comprises a plurality of contacts coupled mechanically to said cam member and electrically to said motor means, said contacts being operable by the rotation of the cam member a predetermined distance in said first direction, to cause said motor means to discontinue operation, thereby to prevent further rotation of said cam member in said first direction.
 8. Apparatus as claimed in claim 7 wherein said contacts are of the elongated resilient type mounted at one end to support means located adjacent said rotating cam member, and at the other end to a cam follower, said follower being in engagement with said cam member for movement thereover as said cam member is rotated, and wherein said cam member includes a plurality of track portions over which said follower is movable, said contacts remaining in an operated condition to maintain said motor means operational so long as said follower is engaging a predetermined one of said track portions, but being moved to an unoperAted condition upon engagement of said follower with another one of said track portions, whereby the operation of said motor means is discontinued.
 9. Apparatus as claimed in claim 7 wherein said contacts are operable by the rotation of said cam member in said opposite direction to discontinue the operation of said motor means upon said cam member returning to its initial position.
 10. Apparatus as claimed in claim 9 wherein said cam member is coupled to each of said pressure applying and wiper means by a corresponding arm member, a first one of said arm members being connected at a first end to said pressure applying means and a second one of said arm members being connected at a first end to said wiper means, said opposite ends of said arm members each being connected to respective follower portions mounted for movement on first and second track portions, respectively, on said cam member each said track portion including a passive section and an active section, whereby movement of a follower portion in said active section causes, through a respective arm member, movement of a corresponding pressure applying or wiper means toward or away from said roller surface, depending upon the direction of rotation of said cam member.
 11. Apparatus as claimed in claim 10 wherein the cam follower of said second arm member is moved over said active section of the track portion initially during the rotation of said cam member in said first direction and wherein the cam follower of said first arm member is moved over said active section of the track portion at a subsequent time during the rotation of said cam member in said first direction, whereby said wiper means is moved into engagement with said roller surface a predetermined time prior to said pressure applying means.
 12. Apparatus as claimed in claim 6 wherein said wiper means and pressure applying means are moved into engagement with said roller surface in sequence, said wiper means being moved into engagement with said roller surface a predetermined time prior to said pressure applying means.
 13. Apparatus as claimed in claim 12 wherein said circuit control means includes delay means for providing a predetermined delay between the engagement of said wiper means and said pressure applying means, thereby to permit said wiper means to uniformly distribute developer liquid over the surface of said roller prior to the engagement of the latter by said pressure applying means.
 14. Apparatus for developing sensitized sheet material by the application to said material of a predetermined quantity of developer liquid, said apparatus comprising: an applicator roller mounted for rotation, said roller having a surface adapted to carry a predetermined quantity of developer liquid, means for rotating said applicator roller in a predetermined direction, a source of developer liquid for application to said applicator roller surface, a wiper blade for removing excess developer liquid from the surface of said roller, said wiper blade mounted adjacent said roller on a support member, said support member being rotatable toward and away from said roller surface for engagement and disengagement, respectively, of said wiper blade, with said roller surface, a pressure blade mounted adjacent said roller on a support member, said support member being rotatable toward and away from said roller surface for engagement and disengagement, respectively, of said pressure blade with said roller surface, a cam member mounted for rotation adjacent said roller and coupled to each of said support members, means for rotating said cam member to provide movement of said blades through said support members, and control means for operating said apparatus, including electrical circuit means connected to said means for rotating said applicator roller and said means for rotating said cam member, said electrical circuit means including switch means actuable to on and off positions whereby upon actuation of said switch means to The on position, said applicator roller is caused to be rotated and said cam member is rotated to move said blades into engagement with said roller surface, and upon actuation of said switch to the off position the rotation of said applicator roller ceases and said blades are moved out of engagement with said roller surface.
 15. Apparatus as claimed in claim 14 further including means mounted adjacent said roller for dispensing developer liquid onto said wiper blade for application thereby to said roller surface, and pump means interconnecting said source and said dispensing means, and wherein said pump means is coupled to said control means, whereby upon operation of said switch means to said on position, said pump means is activated to pump developer liquid from said source to said dispensing means, and upon operation of said switch to said off position, said pump means is deactivated.
 16. Apparatus as claimed in claim 14 wherein said wiper and pressure blade support members are connected to said cam member by means of arm members, each of said arm members being connected pivotally at a first end to said support member and connected at the opposite end to said cam member, whereby rotational movement of said cam member is translated through said arm members to said blade support members.
 17. Apparatus as claimed in claim 16 wherein said electrical circuit means includes contact means operated in accordance with the rotation of said cam member, and wherein said cam member is rotated by means of motor means coupled electrically to said contact means and said switch means, whereby upon the actuation of said switch means said motor means is energized to rotate said cam member in a first direction, said contact means being operable in response to the rotation of said cam member a predetermined distance in said first direction to deenergize said motor means, thereby preventing further rotation of said cam member.
 18. Apparatus as claimed in claim 14 wherein said wiper blade is moved into engagement with said roller surface a predetermined time prior to said pressure blade. 